Hypericum perforatum |
Hypericum radfordiorum |
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Chase-devil, common St. John's-wort, Klamath weed, millepertuis commun, Tipton's weed |
brushy mountain St. Johnswort |
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Habit | Herbs perennial, erect or ± spreading, branching at base and beyond, (3–)4–7(–7.8) dm. | |
Stems | internodes 4-lined. |
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Leaves | ascending to widely spreading, sessile; blade narrowly lanceolate (linear-lanceolate on axillary branches), 10–40(–55) × 5–10(–13) mm, longer than internodes, leathery, margins plane, apex acute to acuminate, densely gland-dotted, basal vein 1, midrib with inconspicuous branches. |
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Inflorescences | cylindric, to 40-flowered; branching mostly dichasial, subsidiary branches usually with relatively smaller leaves. |
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Flowers | 8–15+ mm diam.; sepals lanceolate, unequal (outer slightly wider than inner), 3–6(–7.5) × 1.1–1.8(–2.2) mm, margins sometimes ciliate, not setulose-ciliate, apex acute or acuminate; petals orange-yellow, obovate, 5–10 mm; stamens 50–80, filaments basally connate; styles 2–4 mm; stigmas capitate. |
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Capsules | ovoid, 5 × 3–4 mm. |
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Seeds | 0.4–0.8 mm; testa linear-pitted. |
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2n | = 24. |
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Hypericum perforatum |
Hypericum radfordiorum |
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Phenology | Flowering late spring–fall (May–)Jun–Sep(–Oct). | |
Habitat | Granitic outcrops | |
Elevation | 500–800 m (1600–2600 ft) | |
Distribution |
AR; CA; CO; CT; DC; DE; IA; ID; IL; IN; KS; KY; MA; MD; ME; MI; MN; MO; MT; NC; ND; NE; NH; NJ; NM; NV; NY; OH; OK; OR; PA; RI; SC; SD; TN; TX; VA; VT; WA; WI; WV; WY; BC; MB; NB; NF; NS; ON; PE; QC; Europe; Asia (sw Arabia, China, India, Mongolia, Siberia); n Africa [Also introduced widely elsewhere]
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NC |
Discussion | Subspecies 4 (1 in the flora). Hypericum perforatum has been introduced into various parts of the world, including North America, where only subsp. perforatum is represented. The range of variation in the flora area is less than occurs in Europe, and signs of hybridization that are common there are absent in North America. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Source | FNA vol. 6, p. 99. | FNA vol. 6, p. 90. |
Parent taxa | Hypericaceae > Hypericum > sect. Hypericum | Hypericaceae > Hypericum > sect. Brathys |
Sibling taxa | ||
Subordinate taxa | ||
Name authority | Linnaeus: Sp. Pl. 2: 785. (1753) | Weakley ex J. R. Allison: Castanea 76: 110, fig. 3. (2011) |
Web links |
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